Helix winding machine



Nov. 7, 1961 J. R. DE PRADO HELIX WINDING MACHINE 5 Sheets-Sheet 1 Filed Sept. 1, 1959 R O T N E V m Joy/v /P. 05 PM Do Nov. 7, 1961 J. R. DE PRADO HELIX WINDING MACHINE 3 Sheets-Sheet 2 Filed Sept. 1, 1959 INVENTOR z/owv 05/9 9400 ATTO NEY Nov. 7, 1961 J. R. DE PRADO HELIX WINDING MACHINE Filed Sept. 1, 1959 5 Sheets-Sheet 5 INVENTOR (/Ol/N R. DEPRADO ATT NEY United States Patent ice 3 0 WINDING MACHINE John R. De Prado, Lyn'brook, N.Y., assignor to' Sperry Rand Corporation, Great Neck, N.Y., a corporation of Delaware Filed Sept. 1, 1959, Ser. No. 837,426 12 Claims. (Cl. 153-67) The present invention relates to a helix winding machine, and more particularly, to such a machine which is readily adapted to wind helices of different pitches and/ or diameters, or a single helix having a continuously varying pitch along at least a portion of its length.

In the manufacture of electronic traveling wave tubes, it is necessary to produce accurate wire helices of various sizes, and in some instances it is required to produce helices whose pitches vary along their respective lengths in a predetermined manner. Known helix winding machines of simple design are not readily adaptable to wind helices of different pitches and/or different diameters, and few are capable of accurately winding a helix having a pitch which varies along the length of the helix.

It therefore is an object of the present invention to provide a helix winding machine for winding a helix having a non-uniform pitch along its length.

Another object of this invention is to provide a helix winding machine which is simply and readily adjustable to produce helices of different pitches and/or different diameters.

A further object of this invention is to provide a simply operating helix winding machine for accurately wind- FIGS. 4 and 5 are enlarged views of a portion of the winding head of the present invention and are used to aid in the description of the operation of the device of this invention; 7

FIGS. 6 and 7 are top and side views, respectively, of an alternative winding head constructed in accordance with the present invention; and

FIGS. 8 and 9 are side and end views, respectively, of another embodiment of a winding head constructed in accordance with this invention.

Referring now more particularly to the embodiment of the invention illustrated in FIGS. 1-3, the winding machine is comprised of a base 11 having upstanding end members 12 and 13 at opposite ends thereof. Ex-

tending between end members 12 and 13, on opposite sides thereof, are two rails 14 and 15. A carriage 16 rides longitudinally on said rails by means of rollers and 31. Extending through carriage 16 is a hollow shaft 17 which is free to rotate about its axis by means of bearings 19 and 20, FIG. 2. A gear wheel 18 is secured to hollow shaft 17 and is rotated by means of worm gear 23 secured to the shaft of a motor 24. A chuck 21 is secured to the left end of hollow shaft 17 and engages a mandrel 22.

A winding head 25 is supported on' upstanding end 13 and is comprised of a cylinder 26 disposed adjacent mandrel 22. The cylindrical axis of cylinder 26 is parallel to the longitudinal axis of said mandrel. Winding head 25 further includes a V-shaped notched member 29, FIG. 3, which is disposed on the side of mandrel 22 diametrically opposite cylinder 26. Disposed on cylinder around the circumference of cylinder 26 in non-para leilv relationship to each other. Wire-guiding means 27 a1id 28 extend outwardly frofn fihe surface'pf cylinder 26.

Wire-guiding means 27 and 28 are spaced from mandrel 22 by a distance less than the diameter of the wire to be found on helix 22. Leading Wire-guiding means 27 is adapted to receive a length of free wire and to guide it into contact with mandrel 22. Following wire-guiding means 28 is adapted to slidably engage a formed convolution of the helix on mandrel 22 in a manner to be explained in more detail hereinafter. As best seen in FIGS. 2 and 3, cylindrical member 26 has axially extending rods 32 and 33 which pass through bearing members 34 and 35. Bearing members 34 and 35 are connected to set screws 36 and 37, respectively, by means of springs 38 and 39 so that cylinder 26 is transversely adjustable in position relative to mandrel 22. Notched member 29 also is transversely movable with respect to mandrel 22 by means of set screws 40 and 41.

A cam member 42 having a longitudinally extending cam surface is secured to carriage 16. A cam follower said mandrel.

arm 42, FIGS. 2 and 3, is secured to axially extending shaft 33 of cylinder 26, and rides on cam 42 by means of roller 44. As illustrated in FIG. 3, an L-shaped arm 45 is secured to arm 43 by means of a pivot joint 46, and follows along cam 42 by means of roller 47. A spring 48 connected between arms 43 and 45 assures that arm 43 will accurately follow along the cam surface on cam 42. It thus may be seen that as roller 44 follows along cam 42, arm 43 will be raised or lowered in accordance with the cam surface, and in turn will rotate cylinder 26 about its cylindrical axis.

In the operation of the device illustrated in FIGS. 1-3, the positions of cylinder 26 and notch-shaped member 29 are adjusted by means of set screws 36, 37 and 40, 41, respectively, so that each of said members are separated from mandrel 22 by a distance less than the diameter of the wire to be Wound on mandrel 22. A length of wire is secured to mandrel 22 by some convenient means such as by a clamp, or by passing said wire through a hole in The mandrel 22 is then rotated several times to form several convolutions of wire thereon. One of the formed convolutions, the last-completed convolution for example, is positioned on the side of wire-guiding means 28 most distant from the wire-guiding means 27, FIGS. 4 and 5, and the length of free wire, indicated at 51 in said figures, is passed through wire-guiding means 27, and the end of said free length of wire is supported in some non-stressing manner, as by a gas filled balloon, as illustrated in FIGS. 1 and 3, for reasons which will be 1 explained hereinbelow.

Motor 24 is then energized and causes mandrel 22 to rotate about its axis by means of the mechanism comprised of worm gear 23, gear wheel 18, shaft 17, and chuck 21. As mandrel 22 rotates, the last-formed convolution of the helix rides against the surface of wireguide 28. This last-formed convolution is sufficiently tight on mandrel 22 so that as it rides against wire-guiding means 28 during rotation, it will remain fixed on the mandrel and will act as a screw thread to cause an axial movement of mandrel 22 and carriage 16 attached thereto. The free length of wire 51 is drawn through wireguiding means 27 and onto the rotating and axially moving mandrel 22, thus forming a helix whose pitch is determined by the spacing between wire-guiding means 27 and 28. Thus, the helix is self-generated as the mandrel rotates.

As the helix is formed on mandrel 22, the mandrel and helix thereon are supported between the surface of springloaded cylinder 26 and the grooved surfaces ofnotchshaped member 29, thus preventing bowing of the mandrel.

As may be seen in FIG. 1, carriage 16 will move longitudinally toward the left as the helix is formed on mandrel 22. Cam 42, attached to carriage 16, also moves longitudinally as the helix is formed. As cam 42 moves toward the left, cam following arm 43, FIG. 3, which rides on the cam surface by means of roller 44, will be raised or lowered in accordance with the contour of the cam surface. Cam following arm 43 is a lever arm which is attached to cylinder 26 through axially extending shaft 35, and as arm 43 is raised or lowered by the cam surface, cylinder 26 will rotate and will cause leading and following wire-guiding means 27 and 28 to move transversely past mandrel 22 and will bring different portions of wire-guiding means 27 and 28 into contact with the length of free wire and with the last-formed convolution of the helix, respectively. Inasmuch as wire-guiding means 27 and 28 are not parallel to each other around the surface of cylinder 26, the axial spacing between members 27 and 28 will vary as cylinder 26 is rotated about its axis. This causes the pitch of the helix to vary in accordance with the contour of cam 42. A comparison of FIGS. 4 and 5 will indicate how the pitch of the helix is varied as the pitch-determining cylinder 26 is rotated to different positions so that the axial spacing between wire-guiding means 27 and 28 is different. The contour of cam 42 will be so chosen as to produce the desired variation in the pitch of the helix being wound on mandrel 22.

Winding head 25 readily may be adjusted to accommodate different sized mandrels by adjusting set screws 36, 37 and 40, 41 associated with cylinder 26 and notchshaped member 29, respectively. These are the only adjustments necessary inasmuch as the length of free Wire enters into the winding head from the top, and because it is freely suspended by a balloon 52, as shown in FIGS. 1 and 3, the wire will always come into contact with mandrel 22 along a tangent to said mandrel.

I have found that the uniformity of the pitch of the helix is significantly improved by allowing the length of free wire to be in a substantially non-stressed condition when it comes into contact with mandrel 22. In some helix winding machines constructed in the past, wire-tensioning means have been used to hold the Wire taut so that it was under tension as it came into contact with the mandrel. I have discovered, however, that as the wire winds onto the mandrel, it has a tendency to roll, or rotate, as a result of the generation of the helix. Because the wire is held taut in the wire-tensioning means, the wire coming onto the mandrel is not free to rotate. This has a tendency to put stresses and strains on the wire and the wire will experience some kinking as it is wound onto the mandrel. This is deleterious to the uniformity of the pitch of the helix. By suspending the length of free wire from a balloon 52, FIG. 1, the length of free wire is free to rotate and is substantially in a non-stressed condition as it enters into contact with mandrel 22. In this manner, I have produced constant pitch helices whose uniformity of pitch was much improved over the pitches of helices which were wound with the wire under tension. Other means of supporting the length of free wire in a non-stressed manner may be employed if desired.

In the winding machine illustrated in FIGS. 1-3, winding head 25 is fixed in position with respect to the frame of the machine while mandrel 22 is movable axially with carriage 16. In an alternative arrangement, winding head 25 may be attached to movable carriage 16 and mandrel 25, motor 24, and the linking mechanism therebetween may be fixe'd with respect to the frame of the machine. The operation of this embodiment of the machine would be substantially identical With the operation described above, except winding head 25 and movable carriage 16 would move longitudinally along mandrel 22 as the helix is wound on said mandrel.

In the event that the machine illustrated in FIGS. 1-3 is to be used to wind a plurality of helices, each having a uniform pitch, but the pitches of the helices differing from each other, the cam and cam following mechanism 42-58 may be removed and an indexing mechanism may be attached to rod 33 extending axially from cylinder 26 to rotate the cylinder to the desired positions.

An alternative embodiment of a winding head constructed in accordance with this invention is illustrated in FIGS. 6 and 7 wherein winding head 25 is supported on movable carriage 16 which is adapted to move 10ngitudinally on rails 14 and 15 by means of rollers 30 and 31. A transversely extending key 60 secured to carriage 16 engages frame assembly 63. Bearings 64 and 65 in frame assembly 63 rotatably support cylinder 26. On the side of mandrel 22 opposite cylinder 26, notched member 29 also engages key 60. Both the frame assembly 63 and notch-shaped member 29 are slidable transversely on key 60. Set screws 66 and 67 hold the frame assembly 63, thus cylinder 26, and notch-shaped member 29, in any desired transverse position with re spect to mandrel 22. A pinion gear 68 is secured to a shaft extending axially from the right side of cylinder 26. A rack gear 69 is slidably supported in frame assembly 63 and engages the teeth of pinion gear 68 to form a rack and pinion mechanism. A vertical shaft 70, FIG. 7, is attached to the bottom of rack 69, and a roller 71 is rotatably secured to the bottom of shaft 70. Roller 71 rides on a cam surface 72 which is fixed with respect to the frame of the winding machine.

In this embodiment of the invention, winding head 25 and carriage 16 move longitudinally along mandrel 22 as the helix is formed on mandrel 22 in the self generating manner previously explained. As winding head 25 moves along mandrel 22, roller 71 will follow along cam 72 and will move rack 69 up or down in accordance with the contour of cam 72. As rack 69 moves up and down, a rotary motion will be imparted to cylinder 26 through pinion gear 68. This causes lead ing and following Wire-guiding means 27 and 28 to move transversely past mandrel 22 thus causing different pot" tions of wire-guiding means 27, 28 to be positioned im-' mediately adjacent mandrel 22, and in the manner described above, the pitch of the helix being wound on mandrel 22 will be varied in accordance with the variation in the axial spacing between said two Wire-guiding means.

An alternative form of a winding head constructed in accordance with the present invention is illustrated in FIGS. 8 and 9. In this embodiment, the pitch-determining member is a straight elongated member which is adapted to move tangentially past mandrel 22, rather than being a rotatable cylinder as in the previous embodiments.- Pitch-determining member 80 is supported in a verticalposition adjacent mandrel 22 by means of studs 81 and 82 which extend outwardly from notch-shaped member 29. Said studs extend through an elongated slot 83 in the pitch-determining member, and a spring 84 on stud 81 urges pitch-determining member 80 into contact with mandrel 22. Mandrel 22 is supported on its opposite side within the V-shaped groove in member 29. A roller 85 is rotatably supported in a fork 86 atthe lower end of pitch-determining member 80. Roller 85 is disposed to ride upon a linear cam 89 so as to impart vertical displacement to pitch-determining member 80 as it moves along the cam surface. Pitch-determining member 80 has straight, non-parallel edges 87, 88 which comprise the two wire-guiding means in this embodiment. An elongated member 90 extending parallel to edge 87 of pitchdetermining member 80 helps to guide the length of free wire 91 onto mandrel 22. In this embodiment, the notchshaped member 29 may be affixed to the frame of the machine, and mandrel 22 may be rotatably secured to a movable carriage as in FIGS. 1-3, 'or the winding head may be attached to the movable carriage and the mandrel 22 and cam 89 may be secured to the frame of the machine.

In the operation of this embodiment, pitch-determining member 80 will be raised or lowered as it rides along cam 89 by means of roller 85. This will cause difierent portions of pitch-determiningq member 80 to be positioned adjacent mandrel 22, and because the edges 87 and 88 are non-parallel, the spacing therebetween will vary in accordance with the contour of cam 86. Edge 88 of member 80 rides against the last-formed convolution of the helix on mandrel 22, and edge 87 of member 80 determines the position where the length of tree wire 91 comes into contact with mandrel 22. Therefore, the pitch of the helix being wound on mandrel 22 will vary in accordance with the vertical displacement of pitch determining member 80.

While the invention has been described in its preferred embodiments, it is to be understood that the words which have been used are words of description rather than of limitation and that changes within the purview of the appended claims may be made without departing from the true scope and spirit of the invention in its broader aspects.

What is claimed is:

l. A helix winding machine for winding helices having varying pitch comprising a mandrel disposed along an axis, means for rotating said mandrel about said axis, a winding head disposed adjacent said mandrel and adapted to receive a length of free wire and to form a wire helix on said mandrel, said mandrel and said winding head being movable relative to each other in a direction parallel to said axis, said winding head having a pitch-determining member comprised of axially spaced elongated leading and following wire-guiding means, said two wireguiding means being fixed relative to each other and the axial spacing between said two wire-guiding means varying in a predetermined manner along their lengths, said leading wire-guiding means being radially separated from said mandrel by a distance less than the diameter of said wire to be wound and being adapted to engage said length of free wire in a non-stressing manner and to guide it into contact with said mandrel, said following wire-guiding means being adapted to engage a formed convolution of said helix, said pitch determining member being movable transversely past said mandrel to position ditferent portions of said axially spaced leading and following wireguiding means into engagement, respectively, with said length of free wire and said formed helix, whereby the pitch of said helix is varied in accordance with the variation of axial spacing between said two wire-guiding means.

2. A helix winding machine for winding helices having varying pitch comprising a mandrel disposed along an axis, means for rotating said mandrel about said axis, a winding head disposed adjacent said mandrel and adapted to receive a length of free wire and to form a wire helix on said mandrel, said mandrel and said winding head being movable relative to each other in a direction parallel to said axis, said winding head having axially spaced, elongated leading and following wire-guiding means, the axial spacing between said wire-guiding means varying in a predetermined manner along their lengths, said leading wire-guiding means being radially separated from said mandrel by a distance less than the diameter of the wire to be wound and being adapted to engage said length of free wire and to guide it into con tact with said mandrel, said following wire-guiding means being adapted to engage a formed convolution of said helix, said two wire-guiding means being movable transversely past said mandrel to position different portions of said two axially spaced wire-guiding means into engagement, respectively, with said length of free Wire and said formed helix, thereby to change the axial spacing between the respective points of engagement of said two wire-guiding means with said formed convolution of the helix and said length of free wire, whereby the pitch 6 of said helix is varied in accordance with thevariation in axial spacing between said two wire-guiding means.

3. The combination as claimed in claim 2 including means for moving said two wire-guiding means transversely past said mandrel in a predetermined manner as said mandrel and said winding head move axially relative to each other.

4. A helix winding machine comprising a mandrel disposed along an axis, means for rotating said mandrel about said axis, a winding head positioned adjacent said mandrel, said mandrel and said winding head being movable relative to each other in a direction parallel to said mandrel, said winding head comprising an elongated pitchdetermining member having axially spaced leading and following edges, said edges being axially spaced in a predetermined varying manner along their lengths, said leading edge being adapted to engage a length of free wire and to guide it into contact with said mandrel, said following edge being adapted to engage a formed convolution of said helix on the side of said convolution nearest said leading edge, the edges of said pitch-determining member being transversely movable past said mandrelto position different portions of said following and leading edges into engagement, respectively, with said formed helix and said free wire, thereby to change the spacing between the respective points of engagement of said two edges with said formed convolution of the helix and said length of free wire.

5. The combination as claimed in claim 4 wherein said pitch-determining member is a flat bar adapted to move transversely With respect to said mandrel.

6. The combination as claimed in claim 2 wherein said pitch-determining member is a cylindrical shaped member which is rotatable about its cylindrical axis extending parallel to the longitudinal axis of said mandrel, and said wire-guiding means are comprised of radially protruding members extending around said cylindrical shaped member.

7. The combination as claimed in claim 2. wherein said winding head includes a notch-shaped member fixed to said carriage on the side of said mandrel opposite said pitch-determining member, said notch-shaped member being positioned to engage and thereby support a length of a helix formed on said mandrel.

8. A helix winding machine for winding helics having varying pitch comprising a rotatable mandrel disposed along an axis, a winding head positioned adjacent said mandrel, said mandrel and said winding head being movable relative to each other in a direction parallel to said axis, said winding head comprising a rotatable cylindrical shaped pitch-determining member disposed adjacent said mandrel and having its cylindrical axis parallel to the longitudinal axis of said mandrel, said pitch-determining member having two elongated axially spaced wire-guiding means extending around its surface, the axial spacing between said two wire-guiding means varying in a predetermined manner around the circumference of said pitch-determining member, the first one of said wireguiding means being adapted to engage said length of free wire and to guide it into contact with said mandrel, the second of said wire-guiding means being adapted to engage a formed convolution of a helix on said mandrel on the side of said convolution nearest said first wireguiding means, whereby said second wire-guiding means follows the formed convolutions of said helix and imparts relative axial movement between said winding head and said mandrel as said mandrel rotates, and means coupled to said cylindrical pitch-determining member for rotating said member about its axis in accordance with a predetermined function of its axial movement relative to said mandrel.

9. A helix winding machine for winding helices having varying pitch comprising a rotatable mandrel disposed along an axis, a winding head positioned adjacent said mandrel and adapted to receive a length of wire and to of said mandrel, said pitch-determining member having two elongated axially spaced wire-guiding means extending around its surface, the axial spacing between said two wire-guiding means varying in a predetermined manner around the circumference of said pitch-determining member, the first one of said wire-guiding means being adapted to engage said length of free wire and to guide it into contact with said mandrel, the second of said wire-guiding means being adapted to slidably engage a formed convolution of a helix on said mandrel, whereby said second wire-guiding means follows the formed convolutions of said helix and imparts relative axial movement between said winding head and said mandrel as said mandrel rotates.

10. A helix winding machine for winding helices having varying pitch comprising a mandrel disposed along an axis, means for rotating said mandrel about said axis, a winding head disposed adjacent said mandrel and adapted to receive a length of free wire and to form a wire helix on said mandrel, said mandrel and said winding head being movable relative to each other in a direction parallel to said axis, said winding head having axially spaced, elongated leading and following wire-guiding means, the axial spacing between said Wire-guiding means varying in a predetermined manner along their lengths, said leading wire-guiding means being radially separated from said mandrel by a distance less than the diameter of the Wire to be wound and being adapted to engage said length of free wire and to guide it into contact with said mandrel,

means for supporting said length of free wire in a substantially non-stressing manner, said following wire-guiding means being adapted to slidably engage a formed convolution of a helix on said mandrel, said two wireguiding means being movable transversely past said mandrel to position different portions of said two axially spaced wire-guiding means into engagement, respectively, with said length of free wire and said formed helix, whereby the pitch of said helix is determined by the axial spacing between said two Wire-guiding means at the respective points of engagements with said length of free wire and said convolution of the formed helix.

11. A helix winding machine for winding helices having varying pitch comprising a mandrel disposed along an axis, means for rotating said mandrel about said axis, a winding head disposed adjacent said mandrel and adapted to receive a length of free wire and to form a wire helix on said mandrel, said mandrel and said winding head being movable relative to each other in a direction 'parallel to said axis, said winding head having a pitch-determining member comprised of axially spaced elongated leading and following wire-guiding means, the axial spac- 8 ing between said two wire-guiding means varying in a predetermined manner along their lengths,.said leading wire-guiding means being radially separated from said mandrel by a distance less than the diameter of said wire to be wound and being adapted to engage said length of free wire and to guide it into contact with said mandrel,

said following wire-guiding means being adapted to en-- gage a convolution of a helix on said mandrel, said wireguiding means being movable transversely past said mandrel to position different portions of said axially spaced leading and following wire-guiding means into engagement, respectively, with said length of free wire and said formed helix, whereby the pitch of said helix is varied in accordance with the variation in axial spacing between said two wire-guiding means, and means cooperating with said winding head for moving said wire-guiding means transversely past said mandrel in a predetermined manner in accordance with the relative axial displacement between said mandrel and said winding head.

12. A helix winding machine comprising a mandrel disposed along an axis, means for rotating said mandrel about said axis, a winding head positioned adjacent said mandrel, said mandrel and said winding head being movable relative to each other in a direction parallel to said mandrel, saidwinding head comprising an elongated pitch-determining member having axially spaced leading and following edges, said edges being fixed relative to each other and axially spaced in a predetermined varying manner along their lengths, said leading edge being adapted to engage a length of free wire and to guide it into contact with said mandrel, said following edge being adapted to engage a formed convolution of said helix on the side of said convolution nearest said leading edge, the edge of said pitch-determining member being transversely movable past said mandrel to position ditferent portions of said following and leading edges into engagement, respectively, with said formed convolution of the helix and said free wire, thereby to change the axial spacing between the respective points of engagement of said two edges with said formed convolution of the helix and said length of free wire.

References Cited in the file of this patent UNITED STATES PATENTS 

